The invention relates to a refrigerant compressor having compressor parts slidable relative to each other with a lower friction coefficient in the presence of a specific lubricant so as to reduce, when used in an automotive air conditioner, engine load during air conditioning and thereby improve engine fuel efficiency. The invention also relates to a process for controlling sliding friction between the compressor parts of the refrigerant compressor.
Refrigerant compressors for air conditioners and refrigerators are broadly divided into two broad categories: wobble-plate types (variable displacement types) and rotary-vane types. Each type of refrigerant compressor has a component part slidably held on a bearing or slidably contacted with any other iron-based part. These sliding parts are lubricated with a refrigeration oil. In general, the refrigeration oil contains therein a few percent of phosphorus-based extreme-pressure agent and alcohol friction modifier as disclosed in Japanese Laid-Open Patent Publication No. 10-265790.